Merge pull request #7252 from jitendrapurohit/CRM-17507

Cleanup deprecated CRM_Core_BAO_Settings calls CRM-17507

diff --cc CRM/Contribute/Form/Contribution/Confirm.php
Simple merge

diff --cc CRM/Event/BAO/Event.php
Simple merge

diff --cc CRM/Event/BAO/Participant.php
Simple merge

diff --cc CRM/Mailing/BAO/Mailing.php
Simple merge